Files
hermes-agent/agent/context_references.py
Teknium 83043e9aa8 fix: add timeout to subprocess calls in context_references (#3469)
_expand_git_reference() and _rg_files() called subprocess.run()
without a timeout. On a large repository, @diff, @staged, or
@git:N references could hang the agent indefinitely while git
or ripgrep processes slow output.

- Add timeout=30 to git subprocess in _expand_git_reference()
  with a user-friendly error message on TimeoutExpired
- Add timeout=10 to rg subprocess in _rg_files() returning
  None on timeout (falls back to os.walk folder listing)

Co-authored-by: memosr.eth <96793918+memosr@users.noreply.github.com>
2026-03-27 17:51:14 -07:00

493 lines
16 KiB
Python

from __future__ import annotations
import asyncio
import inspect
import json
import mimetypes
import os
import re
import subprocess
from dataclasses import dataclass, field
from pathlib import Path
from typing import Awaitable, Callable
from agent.model_metadata import estimate_tokens_rough
REFERENCE_PATTERN = re.compile(
r"(?<![\w/])@(?:(?P<simple>diff|staged)\b|(?P<kind>file|folder|git|url):(?P<value>\S+))"
)
TRAILING_PUNCTUATION = ",.;!?"
_SENSITIVE_HOME_DIRS = (".ssh", ".aws", ".gnupg", ".kube")
_SENSITIVE_HERMES_DIRS = (Path("skills") / ".hub",)
_SENSITIVE_HOME_FILES = (
Path(".ssh") / "authorized_keys",
Path(".ssh") / "id_rsa",
Path(".ssh") / "id_ed25519",
Path(".ssh") / "config",
Path(".bashrc"),
Path(".zshrc"),
Path(".profile"),
Path(".bash_profile"),
Path(".zprofile"),
Path(".netrc"),
Path(".pgpass"),
Path(".npmrc"),
Path(".pypirc"),
)
@dataclass(frozen=True)
class ContextReference:
raw: str
kind: str
target: str
start: int
end: int
line_start: int | None = None
line_end: int | None = None
@dataclass
class ContextReferenceResult:
message: str
original_message: str
references: list[ContextReference] = field(default_factory=list)
warnings: list[str] = field(default_factory=list)
injected_tokens: int = 0
expanded: bool = False
blocked: bool = False
def parse_context_references(message: str) -> list[ContextReference]:
refs: list[ContextReference] = []
if not message:
return refs
for match in REFERENCE_PATTERN.finditer(message):
simple = match.group("simple")
if simple:
refs.append(
ContextReference(
raw=match.group(0),
kind=simple,
target="",
start=match.start(),
end=match.end(),
)
)
continue
kind = match.group("kind")
value = _strip_trailing_punctuation(match.group("value") or "")
line_start = None
line_end = None
target = value
if kind == "file":
range_match = re.match(r"^(?P<path>.+?):(?P<start>\d+)(?:-(?P<end>\d+))?$", value)
if range_match:
target = range_match.group("path")
line_start = int(range_match.group("start"))
line_end = int(range_match.group("end") or range_match.group("start"))
refs.append(
ContextReference(
raw=match.group(0),
kind=kind,
target=target,
start=match.start(),
end=match.end(),
line_start=line_start,
line_end=line_end,
)
)
return refs
def preprocess_context_references(
message: str,
*,
cwd: str | Path,
context_length: int,
url_fetcher: Callable[[str], str | Awaitable[str]] | None = None,
allowed_root: str | Path | None = None,
) -> ContextReferenceResult:
coro = preprocess_context_references_async(
message,
cwd=cwd,
context_length=context_length,
url_fetcher=url_fetcher,
allowed_root=allowed_root,
)
# Safe for both CLI (no loop) and gateway (loop already running).
try:
loop = asyncio.get_running_loop()
except RuntimeError:
loop = None
if loop and loop.is_running():
import concurrent.futures
with concurrent.futures.ThreadPoolExecutor(max_workers=1) as pool:
return pool.submit(asyncio.run, coro).result()
return asyncio.run(coro)
async def preprocess_context_references_async(
message: str,
*,
cwd: str | Path,
context_length: int,
url_fetcher: Callable[[str], str | Awaitable[str]] | None = None,
allowed_root: str | Path | None = None,
) -> ContextReferenceResult:
refs = parse_context_references(message)
if not refs:
return ContextReferenceResult(message=message, original_message=message)
cwd_path = Path(cwd).expanduser().resolve()
# Default to the current working directory so @ references cannot escape
# the active workspace unless a caller explicitly widens the root.
allowed_root_path = (
Path(allowed_root).expanduser().resolve() if allowed_root is not None else cwd_path
)
warnings: list[str] = []
blocks: list[str] = []
injected_tokens = 0
for ref in refs:
warning, block = await _expand_reference(
ref,
cwd_path,
url_fetcher=url_fetcher,
allowed_root=allowed_root_path,
)
if warning:
warnings.append(warning)
if block:
blocks.append(block)
injected_tokens += estimate_tokens_rough(block)
hard_limit = max(1, int(context_length * 0.50))
soft_limit = max(1, int(context_length * 0.25))
if injected_tokens > hard_limit:
warnings.append(
f"@ context injection refused: {injected_tokens} tokens exceeds the 50% hard limit ({hard_limit})."
)
return ContextReferenceResult(
message=message,
original_message=message,
references=refs,
warnings=warnings,
injected_tokens=injected_tokens,
expanded=False,
blocked=True,
)
if injected_tokens > soft_limit:
warnings.append(
f"@ context injection warning: {injected_tokens} tokens exceeds the 25% soft limit ({soft_limit})."
)
stripped = _remove_reference_tokens(message, refs)
final = stripped
if warnings:
final = f"{final}\n\n--- Context Warnings ---\n" + "\n".join(f"- {warning}" for warning in warnings)
if blocks:
final = f"{final}\n\n--- Attached Context ---\n\n" + "\n\n".join(blocks)
return ContextReferenceResult(
message=final.strip(),
original_message=message,
references=refs,
warnings=warnings,
injected_tokens=injected_tokens,
expanded=bool(blocks or warnings),
blocked=False,
)
async def _expand_reference(
ref: ContextReference,
cwd: Path,
*,
url_fetcher: Callable[[str], str | Awaitable[str]] | None = None,
allowed_root: Path | None = None,
) -> tuple[str | None, str | None]:
try:
if ref.kind == "file":
return _expand_file_reference(ref, cwd, allowed_root=allowed_root)
if ref.kind == "folder":
return _expand_folder_reference(ref, cwd, allowed_root=allowed_root)
if ref.kind == "diff":
return _expand_git_reference(ref, cwd, ["diff"], "git diff")
if ref.kind == "staged":
return _expand_git_reference(ref, cwd, ["diff", "--staged"], "git diff --staged")
if ref.kind == "git":
count = max(1, min(int(ref.target or "1"), 10))
return _expand_git_reference(ref, cwd, ["log", f"-{count}", "-p"], f"git log -{count} -p")
if ref.kind == "url":
content = await _fetch_url_content(ref.target, url_fetcher=url_fetcher)
if not content:
return f"{ref.raw}: no content extracted", None
return None, f"🌐 {ref.raw} ({estimate_tokens_rough(content)} tokens)\n{content}"
except Exception as exc:
return f"{ref.raw}: {exc}", None
return f"{ref.raw}: unsupported reference type", None
def _expand_file_reference(
ref: ContextReference,
cwd: Path,
*,
allowed_root: Path | None = None,
) -> tuple[str | None, str | None]:
path = _resolve_path(cwd, ref.target, allowed_root=allowed_root)
_ensure_reference_path_allowed(path)
if not path.exists():
return f"{ref.raw}: file not found", None
if not path.is_file():
return f"{ref.raw}: path is not a file", None
if _is_binary_file(path):
return f"{ref.raw}: binary files are not supported", None
text = path.read_text(encoding="utf-8")
if ref.line_start is not None:
lines = text.splitlines()
start_idx = max(ref.line_start - 1, 0)
end_idx = min(ref.line_end or ref.line_start, len(lines))
text = "\n".join(lines[start_idx:end_idx])
lang = _code_fence_language(path)
label = ref.raw
return None, f"📄 {label} ({estimate_tokens_rough(text)} tokens)\n```{lang}\n{text}\n```"
def _expand_folder_reference(
ref: ContextReference,
cwd: Path,
*,
allowed_root: Path | None = None,
) -> tuple[str | None, str | None]:
path = _resolve_path(cwd, ref.target, allowed_root=allowed_root)
_ensure_reference_path_allowed(path)
if not path.exists():
return f"{ref.raw}: folder not found", None
if not path.is_dir():
return f"{ref.raw}: path is not a folder", None
listing = _build_folder_listing(path, cwd)
return None, f"📁 {ref.raw} ({estimate_tokens_rough(listing)} tokens)\n{listing}"
def _expand_git_reference(
ref: ContextReference,
cwd: Path,
args: list[str],
label: str,
) -> tuple[str | None, str | None]:
try:
result = subprocess.run(
["git", *args],
cwd=cwd,
capture_output=True,
text=True,
timeout=30,
)
except subprocess.TimeoutExpired:
return f"{ref.raw}: git command timed out (30s)", None
if result.returncode != 0:
stderr = (result.stderr or "").strip() or "git command failed"
return f"{ref.raw}: {stderr}", None
content = result.stdout.strip()
if not content:
content = "(no output)"
return None, f"🧾 {label} ({estimate_tokens_rough(content)} tokens)\n```diff\n{content}\n```"
async def _fetch_url_content(
url: str,
*,
url_fetcher: Callable[[str], str | Awaitable[str]] | None = None,
) -> str:
fetcher = url_fetcher or _default_url_fetcher
content = fetcher(url)
if inspect.isawaitable(content):
content = await content
return str(content or "").strip()
async def _default_url_fetcher(url: str) -> str:
from tools.web_tools import web_extract_tool
raw = await web_extract_tool([url], format="markdown", use_llm_processing=True)
payload = json.loads(raw)
docs = payload.get("data", {}).get("documents", [])
if not docs:
return ""
doc = docs[0]
return str(doc.get("content") or doc.get("raw_content") or "").strip()
def _resolve_path(cwd: Path, target: str, *, allowed_root: Path | None = None) -> Path:
path = Path(os.path.expanduser(target))
if not path.is_absolute():
path = cwd / path
resolved = path.resolve()
if allowed_root is not None:
try:
resolved.relative_to(allowed_root)
except ValueError as exc:
raise ValueError("path is outside the allowed workspace") from exc
return resolved
def _ensure_reference_path_allowed(path: Path) -> None:
home = Path(os.path.expanduser("~")).resolve()
hermes_home = Path(
os.getenv("HERMES_HOME", str(home / ".hermes"))
).expanduser().resolve()
blocked_exact = {home / rel for rel in _SENSITIVE_HOME_FILES}
blocked_exact.add(hermes_home / ".env")
blocked_dirs = [home / rel for rel in _SENSITIVE_HOME_DIRS]
blocked_dirs.extend(hermes_home / rel for rel in _SENSITIVE_HERMES_DIRS)
if path in blocked_exact:
raise ValueError("path is a sensitive credential file and cannot be attached")
for blocked_dir in blocked_dirs:
try:
path.relative_to(blocked_dir)
except ValueError:
continue
raise ValueError("path is a sensitive credential or internal Hermes path and cannot be attached")
def _strip_trailing_punctuation(value: str) -> str:
stripped = value.rstrip(TRAILING_PUNCTUATION)
while stripped.endswith((")", "]", "}")):
closer = stripped[-1]
opener = {")": "(", "]": "[", "}": "{"}[closer]
if stripped.count(closer) > stripped.count(opener):
stripped = stripped[:-1]
continue
break
return stripped
def _remove_reference_tokens(message: str, refs: list[ContextReference]) -> str:
pieces: list[str] = []
cursor = 0
for ref in refs:
pieces.append(message[cursor:ref.start])
cursor = ref.end
pieces.append(message[cursor:])
text = "".join(pieces)
text = re.sub(r"\s{2,}", " ", text)
text = re.sub(r"\s+([,.;:!?])", r"\1", text)
return text.strip()
def _is_binary_file(path: Path) -> bool:
mime, _ = mimetypes.guess_type(path.name)
if mime and not mime.startswith("text/") and not any(
path.name.endswith(ext) for ext in (".py", ".md", ".txt", ".json", ".yaml", ".yml", ".toml", ".js", ".ts")
):
return True
chunk = path.read_bytes()[:4096]
return b"\x00" in chunk
def _build_folder_listing(path: Path, cwd: Path, limit: int = 200) -> str:
lines = [f"{path.relative_to(cwd)}/"]
entries = _iter_visible_entries(path, cwd, limit=limit)
for entry in entries:
rel = entry.relative_to(cwd)
indent = " " * max(len(rel.parts) - len(path.relative_to(cwd).parts) - 1, 0)
if entry.is_dir():
lines.append(f"{indent}- {entry.name}/")
else:
meta = _file_metadata(entry)
lines.append(f"{indent}- {entry.name} ({meta})")
if len(entries) >= limit:
lines.append("- ...")
return "\n".join(lines)
def _iter_visible_entries(path: Path, cwd: Path, limit: int) -> list[Path]:
rg_entries = _rg_files(path, cwd, limit=limit)
if rg_entries is not None:
output: list[Path] = []
seen_dirs: set[Path] = set()
for rel in rg_entries:
full = cwd / rel
for parent in full.parents:
if parent == cwd or parent in seen_dirs or path not in {parent, *parent.parents}:
continue
seen_dirs.add(parent)
output.append(parent)
output.append(full)
return sorted({p for p in output if p.exists()}, key=lambda p: (not p.is_dir(), str(p)))
output = []
for root, dirs, files in os.walk(path):
dirs[:] = sorted(d for d in dirs if not d.startswith(".") and d != "__pycache__")
files = sorted(f for f in files if not f.startswith("."))
root_path = Path(root)
for d in dirs:
output.append(root_path / d)
if len(output) >= limit:
return output
for f in files:
output.append(root_path / f)
if len(output) >= limit:
return output
return output
def _rg_files(path: Path, cwd: Path, limit: int) -> list[Path] | None:
try:
result = subprocess.run(
["rg", "--files", str(path.relative_to(cwd))],
cwd=cwd,
capture_output=True,
text=True,
timeout=10,
)
except FileNotFoundError:
return None
except subprocess.TimeoutExpired:
return None
if result.returncode != 0:
return None
files = [Path(line.strip()) for line in result.stdout.splitlines() if line.strip()]
return files[:limit]
def _file_metadata(path: Path) -> str:
if _is_binary_file(path):
return f"{path.stat().st_size} bytes"
try:
line_count = path.read_text(encoding="utf-8").count("\n") + 1
except Exception:
return f"{path.stat().st_size} bytes"
return f"{line_count} lines"
def _code_fence_language(path: Path) -> str:
mapping = {
".py": "python",
".js": "javascript",
".ts": "typescript",
".tsx": "tsx",
".jsx": "jsx",
".json": "json",
".md": "markdown",
".sh": "bash",
".yml": "yaml",
".yaml": "yaml",
".toml": "toml",
}
return mapping.get(path.suffix.lower(), "")